1. Field
Various features relate to serial time-division-multiplexed (TDM) bus systems, particularly audio TDM bus systems for use with wireless computing devices.
2. Background
Advances in technology have resulted in smaller and more powerful mobile or wireless computing devices such as mobile telephones, personal digital assistants and tablet computers. Mobile telephones and tablet computers can communicate voice and data packets over wireless networks. Further, many wireless devices include component devices incorporated therein such as digital still cameras, digital video cameras, digital recorders and audio file players. Also, wireless devices can process executable instructions to provide web browser applications or other software applications.
Insofar as audio processing is concerned, wireless devices can include an audio coder/decoder (CODEC) subsystem and a separate audio processing subsystem. The audio CODEC subsystem may include, for example, one or more CODECs, microphones (MICS), a headphone interface (HPH I/F) and one or more speakers. The audio CODEC subsystem receives audio data from the audio processing subsystem, which is in turn connected to other components of the wireless device. A bus may be provided between the audio CODEC subsystem and the audio processing subsystem such as a Serial Low-power Inter-chip Media Bus (SLIMbus) or other serial time-division-multiplexed (TDM) bus system. The audio CODEC subsystem and the audio processing subsystem may be regarded as state machines that need to be synchronized with one another. In current devices, synchronization is typically performed on every clock cycle of the bus with considerable corresponding software overhead including packet framing and the like.
Therefore, there is a need to provide improved TDM bus systems for use with wireless devices.